The present invention is directed to a chair with a backrest which can be adjusted relative to a seat surface, and, in particular, to such a chair in which the backrest can be adjusted in its inclination independently of the position of the seat of the chair.
Chairs are known that are adjustable between a sitting and a reclining position. These are also known as sitting and reclining furniture. They allow an adjustment of the position between a “normal” upright sitting position and a generally horizontally oriented reclining position. An adjusted inclination of the backrest is maintained or the inclination of the backrest can be adjusted separately and independently of the position of the chair.
German Patent Application No. DE 296 00 282 U1 discloses a chair in which it is possible to perform the adjustment by moving the seat surface without substantial force, since a parallel linkage system moves the body weight or the center of gravity backward along with the seat surface when the seat surface is shifted. The inclination of the backrest is adjusted by a gas pressure spring controlled via a valve, and the valve is activated via an operating lever.
Another chair is known from the firm Steltemeier GmbH located in Lippstadt. In this chair as well, an adjustment of the inclination of the backrest occurs via a gas pressure spring and is controlled by means of operating lever and valve.
In such chairs the mechanism associated with the operating lever may be complicated and prone to breakdown. Furthermore, the user often must operate the lever to adjust the inclination, which may be difficult in the reclining position. Moreover, the operating of the lever may not always be intuitive, depending on its design, and so the user may need to have this explained to him or her.